Microsoft Security AI Research team is seeking a Principal Research Data and Service Engineer to join their applied science team focused on defending Microsoft through applied AI innovation. This role combines cutting-edge AI research with practical security applications, working at the intersection of security, AI, and large-scale systems engineering. The position involves establishing and building processes and structures to empower research scenarios, from data engineering to creating agentic AI systems and security-focused language models. The role offers an opportunity to work with applied scientists to develop systems solving real-world security challenges, utilizing Microsoft's unique position in understanding defensive and offensive security expertise. The team's work directly impacts billions of users worldwide, defending against digital threats and regulatory challenges. The position offers competitive compensation, comprehensive benefits, and the chance to work with state-of-the-art AI technology in security applications.